No doubt one of the most frequently utilized tools of a mechanic, particularly an automotive mechanic, is the socket wrench. This tool comprises a wrench of any one of various types having a square drive element adapted to engage in a snap-fit manner, a square cavity as formed in any one of various sizes of socket elements, the latter destined to captively engage the polygonal periphery of either a nut or the head of a bolt/machine screw. When operating around larger pieces of equipment, such as motor vehicles and construction machinery, the need frequently exists to apply or remove threaded fasteners which are not readily accessible in view of cramped quarters immediately surrounding the fastener. In these cases, one applies an extension element intermediate the wrench and socket and which comprises an elongated element having a female upper end engaged by the wrench drive element and an opposite male end similar in configuration to the wrench drive element and which is snap-fitted into the socket.
A problem encountered when using many existing extensions with socket tool sets is that often when withdrawing the tool assembly from a use position, the socket is pulled from the lower end of the extension element due to an interference fit with the involved nut or bolt head. Thereafter, the socket may fall to an even more inaccessible spot or at least remain attached to the nut or bolt which is already in an awkward location. Thus, it will be highly desirable to have available an extension device for socket tools that automatically will provide a reliable locking action to positively retain sockets on its outer end yet will not call for an inordinate amount of machining or an excessive cost to manufacture. Many attempts at providing mechanisms in this area have been hampered by the extremely cramped space within which to install any supplemental structure. The most popular and often considered the standard size among socket tool sets is considered the 1/2" drive. This means that the square drive stud at the forward end of each extension is but one-half inch wide per face while the maximum diameter usually available throughout the length of the extension shank is approximately 5/8". Then, one must realize that a smaller, 3/8" drive socket tool set also exists and the available room within extensions in this latter size set will be even more restrictive. Thus, extension socket latching mechanisms must maximize use of the limited area available within the confines of elongated extension members and the instant construction proposes a unique solution in this area.